Slurry mixer



W. S.' WHITTLE SLURRY MIXER Filed NOV. l5, 1944 s sheets-sheet;

w. s. WHITTLE 22,4%,626

SLURRY MIXER Filed Nov. 15, 194.4 :s sheets-sheet 2 Feb. 24, 3948.

w. s; WHITTLE 2,436,626

SLURRY MIXER Filed Nov. 15, 1944 3 Sheets-Sheet 3 leale/f arme/yg YJ Patented Feb. 24, 1948 SLURRY 1*' William S. Whittle, University Heights. Ohio. as signor to The Ferro Engineering Company, Cleveland, Ohio, a corporation of Ohio Application November 15, 1944, Serial No. 563,549 3 Claims. (SCH. 259-147) 'I'his invention relates to improvements` in slurry mixers, that is apparatus for mixing together heavy comminuted material and a liquid such as water. The material for-which the invention is intended primarily, known in the iron and steel industry as slurry, is a thick heavy mixture, largely of some crushed, ground or finely divided refractory substance. It has a consistency somewhat like that of buttermilk and a density similar to that of cement, in other words about one hundred pounds per vcubic foot. One of its uses is in the coating of interior surfaces of hot tops to ll cracks in and between lining bricks and to protect the bricks against the heat ofthe molten metal.

One oi the objects of the invention is the provision of apparatus for mixing heavy comminuted material with a. liquid by means of streams of compressed air employed for agitating and aerating the mixture.

Another object is the provision of apparatus oi' the character stated which shall not be subject to excessive wear or maintenance by becoming clogged.

Other objects and features of novelty will appear as I proceed with the description of that embodiment oi. the invention which, for the purposes oi the present application, I have illustrated in the accompanying drawings, in which Fig. 1 is an elevational view, partly broken away and partly in section, illustrating apparatus embodying the invention.

Fig. 2 is a fragmental elevational view taken at right angles to that oi Fig. 1.

Fig. 3 is a plan view with the cover of the tank removed.

Fig. 4 is a vertical sectional view of a delivery means and control valve which may be employed in connection with the invention.

Fig. 5 is a plan view of a cover hopper at the top of the tank.

Figs, 6, and 7 are vertical sectional views on a larger scale taken substantially on the lines 5 6 and 1 1 oi' Fig. 3, and

Fig. 8 is a diagrammatic view in perspective of the manifold and pipe assembly through which agitating and aerating air is introduced into the tank..

In the drawings I have illustrated a tank. the upper portion l0 of which may be cylindrical in shape, while the lower portion is in the form of an inverted cone il having a removable cleanout plug l2 at the bottom thereof. The tank is supported preferably upon tripod legs Ai3 rigidly con,-v

nectecl with the conical portion I I At the top of the tank there is a cover i4 hinged at 9 and provided along three edges with outwardly ilared side flanges i5, so that the cover constitutes a shallow hopper. A round opening it in this cover-is underlaid with a grid i1. A blind spot may be provided at the middle of the grid to augment its function oiV slowing down the rate oi feed of dry material. The opening i8 may be closed by a lid I9 yhinged to the cover as indicated at 20. Water or other liquid may be admitted to the tank through a connection I8, or

one stemming from this point by means of a separate hose. Preferably, a water meter, not shown, is interposed between connection i8 and the water supply for convenience in measuring the quantity admitted to the tank.

The ilrst step in my method of forming the desired mixture is the admission of a measured quantity of water into the tank.v Thereafter, and while the water Ais being agitated, a measured quantity oi dry material is dumped onto the cover hopper ifi, and the dry material vthen -drops gradually through the bars of the grid Il into the Water. This gradual feeding oi the dry material into the water is essential to the success oi the method, for if a quantity of dry material should get into'the tank ln one mass and be wetted on the outside it would form a ball which would be very diilcult to break up.

The means which I employ for agitating the mixture as the dry material is fed into it comprises an assembly or unit of manifolds and pipes illustrated diagrammatically in Fig, 8 and in detail in Figs. 6 and 7. Air under pressure is admitted to an upright pipe 20 of this unit through the wall of the tank at the point 2|- A pair. of metal straps 22 of slightly less length than the inner diameter of the tank are clamped to pipe 20 and to a shorter upright pipe 23 by means of bolts 28 or the like; In alignment with pipes 20 and 23 there are downwardly extending pipes 25 and 26 respectively. T-connections 2l join pipes 20 and 25 and pipes 23 and 26 and also receive the ends of a manifold 28. At the center of mani.. fold 28 there is a cross-connection 2Q from which extend manifold pipes 30 and 3| at right angles to manifold 23 and in the same horizontal plane therewith. At the outer ends of manifold pipes 30 and 3| there are elbows 32 which support downwardly extending pipes 33 and 34. All four of the pipes 25. 26, 33 and 34'have at their lower ends elbows 35 providing horizontally directed nozzles which, as shown in Fig. 3, are disposed at similar angles with respect to the manifold pipes by which they are carried.

The manifold 28 includes in addition to the cross-connection 29. a T-oonnection 36 for supporting a pair of elbows 31 and 38 from which depends a pipe 39 substantially at the center of the assembly. This pipe is longer than the pipes 25, 28, 33 and 34 and extends downwardly nearly to the bottom of the conical part Il of the tank. A pair of metal straps 40, somewhat shorter than the straps 22, are clamped to the pipes 33 and 34 and also to the pipe 39 by means of bolts or the like. The ends of straps 40 are preferably bevelled to nt the slope of the walls of the lower part Il oi the tank and may be permitted to rest on those walls as a means of support for the assembly.

means includesl a horizontal pipe 45 projecting through the wall of the lower conical part il of the tank with the joint between the pipe and tank sealed preferably by a weld. The inner end of this pipe carries a sleeve 48 with a series of peripheral perforations 41.` A soft rubber piston valve 43 slides within this sleeve to permit or out ofi communication between the perforations 41 and the interior of pipe 45. The piston valve 48 is mounted on the inner end of a rod 49, the outer end of which is slidable through a central bore in a plug 50 that is mounted in a T connection 5| which is rotatable upon the pipe 45. This T-connection carries a-pipe 52 which normallv stands in a vertical position asillustrated in Figs. 1 and 4. It also has an arm 53 rigidly connected therewith for the support of a pivot 54 upon which a hand lever 55 is adapted to swing. The lower end of this lever has a pin and slot connection with the outer end of rod 49. Movements of the piston valve 43 to operative and inoperative positions are therefore effected by operation of hand lever 55. A sleeve 56 with a bore slightly larger than the diameter of rod 49 surrounds that rod and is fixed within a socket in plug 50. Grease passages 51 and 53 adapted to be filled by grease inserted through a pressure fitting 59 serve to provide an extended grease cylinder around the rod as a protection against the entrance of the slurry into the bearing in plug 50. The valve 48 is normally drawn outwardly to cover the holes 41./ When a mixing operation is completed and it is desired to deliver the contents of the tank into a suitable receptacle. such for example as a wheeled drum, the pipe 52 is swung down to a substantially horizontal position indicated in broken lines in Fig. 2. Thenthe handle 55 is moved to the position illustrated in Fig. 4 and the slurry flows through 4 holes 41 and through the pipes 45 and 52 into the container.

Operation-As previously stated a measured quantity of water is first placed in the tank. Then the air is turned on by means oi' a manual control valve, not shown. A relatively high pressure, of the order of fifty pounds per square inch, is then available in the manifold pipes 23, 30 and 3|. The constrictions 8| act as reducing valves and the consequent pressure in pipes 25, 28, 33, 34 and 39, the exits of which are closed by the water in the tank, become relatively low pressures, of the order of ten pounds per square inch. The dry material is now introduced gradually, the grid I1 insuring that this will be the case. The low pressure chambers behind the nozzles 35 prevent any backing upof the slurry into the constricted passages 8|, so that there is no clogging or wearing of those passages, as there would be if they were located at the nozzles. The openings at the nozzles are fairly large and clogging at those points is not likely to occur, but if the slurry. after being mixed should be permitted to remain for a time in the tank and if some of it should back up through one of the nozzles into the low pressure chamber above it, thereby blocking the exit of air, the pressure in that chamber would gradually build up until finally it would become high enough to blow out the plugging material and thus clean the nozzle.

A power operated mixer of this kind has a very practical advantage over the ordinary manual mixing means in that the mixing may be continued for whatever length oi' time is found to be necessary to fully complete the operation. A mixing time greater than would be practical for manual operation may be necessary, for example,

where the mixture contains colloidal material which is slow to absorb its full complement of water.

Having thus described my-invention, I claim:

1. In apparatus for mixing slurry or like material, a tank adapted to hold liquid, means for feeding comminuted material gradually into said liquid, an imperforate pipe having a nozzle disposed to discharge into said tank below the liquid level, means for supplying air under pressure to the pipe, and a constriction in the pipe between the said nozzle and the source of supply of said compressed air, providing a low pressure chamber behind the nozzle.

2. In apparatus for mixing slurry or like material, a tank adapted to hold liquid, means for feeding comminuted material gradually into said lquid, a manifold, a plurality of imperforate g pipes connected with said manifold having noz- L ly from said manifold having nozzles at their lower extremities disposed to discharge into said tank below the liquid level,` means for supplying air under pressure to said manifold, and plugs disposed at the connections between said manifold and said pipes. said plugs having constricted passages therethrough for providing low ypressure in the chambers constituted byl said Number Name Date pipes. 1,297,081 Brown Mar. 11, 1919 WILLIAM S. WHITTLE. 1,448,370 Wardell Mar. 13, 1923 1,478,865 Weber Dec. 25, 1923 ylU3FE1m1\TCES CITED 5 1,531,594 Carrozza. et a1 Mar. 31, 1925 The following references are of record in the f 11953391 Westbelg et al ADI'. 371934 nl@ of this patent: 1,998,700 Bell Apr. 23, 1935 2,038,756 Oakes Apr. 28, 1936 UNITED STATES PATENTS 2,090,469 Chorley Aug. 17, 1937 Number Name Date 1 373,345 canmfr Dec, 1o, 1907 FOREIGN PAIENIS 1,137,294 Schroder Apr. 27, 1915 Number Country Date 

